PERUBAHAN BIOLOGIS DAN FISIOLOGIS SEBAGAI INDIKATOR MASAK BENIH KAKAO HIBRIDA

ABSTRAKProgram pengembangan dan rehabilitasi tanaman kakao membutuh-kan benih bermutu. Mutu benih antara lain ditentukan oleh saat panenyang tepat, terutama berhubungan dengan masak fisiologis. Beberapaindikator penting yang berkaitan dengan masak fisiologis benih adalahkarakteristik biologis dan fisiologis. Penelitian telah dilaksanakan diKebun Induk Benih Pusat Penelitian Kopi dan Kakao (Puslitkoka) Jember,Laboratorium Fisika dan Laboratorium Ilmu dan Teknologi Benih IPB,serta Rumah Kaca Balai Penelitan Bioteknologi Perkebunan Indonesia,Bogor pada bulan Februari-September 2008. Penelitian ini bertujuan untuk(1) mempelajari perubahan biologis dan fisiologis selama perkembanganbenih kakao hibrida, (2) mengetahui hubungan antar berbagai karakterbiologis dan fisiologis benih yang mencerminkan mutu benih, dan (3)menentukan saat panen yang tepat benih kakao hibrida TSH 858 xSca 6 dan ICS 60 x Sca 6. Benih yang digunakan berasal dari hasilpersilangan buatan antara kakao TSH 858 x Sca 6 dan ICS 60 x Sca 6.Umur panen benih yang digunakan dalam penelitian adalah 120, 135, 150,165, dan 180 hari yang dihitung saat setelah antesis, dan setiappengamatan diulang 4 kali. Analisis data disajikan dalam bentuk grafikdengan data primer ditambah standar deviasi dalam program Excel danuntuk mengetahui hubungan dari masing-masing karakter mutu benihdilakukan ”analisis path” menggunakan SAS dari Windows v 9.1. Hasilpenelitian menunjukkan dua fase perkembangan benih. Fase perkem-bangan hingga masak fisiologis (fase 1) dan fase setelah masak fisiologis(fase 2) kakao hibrida TSH 858 x Sca 6 dan ICS 60 x Sca 6. Masakfisiologis benih kakao hibrida TSH 858 x Sca 6 tercapai pada saat 150HSA dan ICS 60 x Sca 6 pada 165 HSA. Daya kecambah, indeks vigor,K CT -R, T 50 , bobot basah dan bobot kering benih, karotenoid dan antosianinbenih dan buah, jumlah daun, dan tinggi bibit dari benih kakao hibridaTSH 858 x Sca 6 dan ICS 60 x Sca 6 mencapai maksimum pada saatmasak fisiologis dan menurun pada fase kedua. Selama periodeperkembangan benih terjadi penurunan total klorofil benih dan buah,sedangkan warna buah kuning mengalami peningkatan. Karakter yangberhubungan langsung dengan mutu benih pada saat masak fisiologisbenih kakao hibrida TSH 858 x Sca 6 dan ICS 60 x Sca 6 adalah warnabuah kuning, indeks vigor, total klorofil benih dan buah, karotenoid danantosianin benih, T 50 , tinggi bibit, K CT -R, dan bobot kering benih.Kata kunci: Theobroma cacao, biologi benih, fisiologi benih, karakteristikbenih, mutu benihABSTRACTBiological and Physiological Changes as Indicator ofMaturity of Hybrid Cacao SeedThe development and rehabilitation programs of cacao need highquality seeds. The high quality of cacao seeds is influenced by seedsphysiological maturity and harvesting time. Several important indicatorsrelated to the seed physiological maturity are biological and physiologicalcharacters. The research objectives were: (1) to study biological andphysiological changes during of seed development, (2) to study on thecorrelation of various characteristics related with seeds physiology andquality, (3) to determine the most appropriate harvesting time for hybridcacao seed of TSH 858 x Sca 6 and ICS 60 x Sca 6. The research wasconducted at Coffee and Cacao Research Institute of Indonesia(Puslitkoka) in Jember, IPB Biophysics and Seeds and TechnologyLaboratory and Biotechnology Research Institute for Estate CropsIndonesia glass house in Bogor from February to September 2008. Theseeds were originated from hand pollination of TSH 858 vs Sca 6 and ICS60 vs Sca 6 hybrids from Puslitkoka Jember. The seeds for this researchwere harvested on: 120, 135, 150, 165, and 180 days after anthesis (DAA);with four replications each. Data were analyzed and presented as graphs,standard deviation in excel; while the relationship of each character ofseeds quality was determined using path analysis by SAS for Windows v.9.1. The results showed that the seed physiological changed on two phasesduring its development. The first phase started from seeds development upto physiological maturity for TSH 858 x Sca 6 and as well ICS 60 x Sca 6hybrids, and second phases started after physiological maturity. Thephysiological maturity of each seeds is 150 DAA for TSH 858 x Sca 6 and165 DAA for ICS 60 x Sca 6 hybrids. Seed germination percentage, vigorindex, germination rate (K CT -R and T 50 ), wet and dry weight of seed, seedsand fruits carotenoid content, seed and fruit anthocyanin content, numberof leaves, and height of seedling reached maximum when seed achievedphysiological maturity and decreased afterward. During seed development,there was decreasing of seeds and fruits chlorophyll content and increasedfor the yellow color of fruit. The characters which showed directcorrelation with seeds quality during seed development of TSH 858 x Sca6 and ICS 60 x Sca 6 hybrids are: yellow color of fruit, vigor index,chlorophyll content for seeds and fruit, seed carotenoid and anthocyanincontent, germination rate (T 50, K CT -R), seedling height and seed dry weight.Key words: Theobroma cacao, seed biological, seed physiological, seedcharacteristic, seed quality

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Seed development in Malva parviflora: onset of germinability, dormancy and desiccation tolerance

Australian Journal of Experimental Agriculture ◽

10.1071/ea06078 ◽

2007 ◽

Vol 47 (6) ◽

pp. 683 ◽

Cited By ~ 4

Author(s):

Pippa J. Michael ◽

Kathryn J. Steadman ◽

Julie A. Plummer

Keyword(s):

Moisture Content ◽

Seed Development ◽

Desiccation Tolerance ◽

Dry Weight ◽

Physical Dormancy ◽

Seed Moisture Content ◽

Physiological Maturity ◽

Seed Moisture ◽

Physiological Dormancy ◽

Malva Parviflora

Seed development was examined in Malva parviflora. The first flower opened 51 days after germination; flowers were tagged on the day that they opened and monitored for 33 days. Seeds were collected at 12 stages during this period and used to determine moisture content, germination of fresh seeds and desiccation tolerance (seeds dried to 10% moisture content followed by germination testing). Seed moisture content decreased as seeds developed, whereas fresh (max. 296 mg) and dry weight (max. 212 mg) increased to peak at 12–15 and ~21 days after flowering (DAF), respectively. Therefore, physiological maturity occurred at 21 DAF, when seed moisture content was 16–21%. Seeds were capable of germinating early in development, reaching a maximum of 63% at 9 DAF, but germination declined as development continued, presumably due to the imposition of physiological dormancy. Physical dormancy developed at or after physiological maturity, once seed moisture content declined below 20%. Seeds were able to tolerate desiccation from 18 DAF; desiccation hastened development of physical dormancy and improved germination. These results provide important information regarding M. parviflora seed development, which will ultimately improve weed control techniques aimed at preventing seed set and further additions to the seed bank.

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Modification of Yield and Chlorophyll Content in Leaf Lettuce by HPS Radiation and Nitrogen Treatments

HortScience ◽

10.21273/hortsci.26.11.1371 ◽

1991 ◽

Vol 26 (11) ◽

pp. 1371-1374 ◽

Cited By ~ 5

Author(s):

Cary A. Mitchell ◽

Tina Leakakos ◽

Tameria L. Ford

Keyword(s):

Chlorophyll Content ◽

Photosynthetic Pigment ◽

Dry Weight ◽

Pigment Content ◽

Carotenoid Content ◽

Photon Flux ◽

Specific Content ◽

Nitrogen Treatments ◽

Incandescent Lamps ◽

Leaf Dry Weight

This study evaluated the potential of high photosynthetic photon flux (PPF) from high-pressure sodium (HPS) lamps, alone or in combination with metal halide (MH) plus quartz iodide (QI) incandescent lamps, to support lettuce growth, with or without N supplementation. Varying exposures to radiation from combined HPS, MH, and QI lamps influenced dry weight gain and photosynthetic pigment content of hydroponically grown `Black-Seeded Simpson' lettuce (Lactuca sativa L.) seedlings. Cumulative leaf dry weight declined with increasing exposure, up to 20 hours per day, to 660 μmol·m-2·s-1 of photosynthetically active radiation (PAR) from HPS lamps concomitant with constant 20 hours per day of 400 m mol·m-2·s-1 from MH + QI lamps. Leaves progressively yellowed with increasing exposure to radiation from the three-lamp combination, corresponding to lower specific chlorophyll content but not to specific carotenoid content. Lettuce grown under 20-hour photoperiods of 400, 473, or 668 μmolm·m-2·s-1 from HPS radiation alone had the highest leaf dry weight at a PPF of 473 μmol·m-2·s-1. Chlorophyll, but not carotenoid specific content, decreased with each incremental increase in PPF from HPS lamps. Doubling the level of N in nutrient solution and supplying it as a combination of NH4+ and NO3- partially ameliorated adverse effects of high PPF on growth and pigment content relative to treatments using single-strength N as NO3–.

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SEED DEVELOPMENT AND GERMINATION STUDIES OF TWO TRUE MANGROVE SPECIES RHIZOPHORA MUCRONATA POIR AND BRUGUIERA CYLINDRICA (L) BLUME.

Kongunadu Research Journal ◽

10.26524/krj216 ◽

2017 ◽

Vol 4 (2) ◽

pp. 151-156

Author(s):

Sekaran S

Keyword(s):

Seed Development ◽

Dry Weight ◽

Germination Percentage ◽

Rhizophora Mucronata ◽

Mangrove Species ◽

Physiological Maturity ◽

Seed Collection ◽

The Family ◽

Bruguiera Cylindrica ◽

Collection Time

The present study was carried out on phenological observations and reproductive characteristics including seed development, maturation and number of days taken for produce mature propagules/seeds by the selected two important mangrove species Rhizophora mucronata . Prior Bruguiera cylindrical (L) Blume ofthe family Rhizophoraceae. An interesting adaptation noticed in true mangroves is that or those belonging to the family Rhizhophoraceae reproduce through a unique biological phenomenon called vivipary. In this mode of reproduction in the post fertilization the zygotes stay on the mother plant for a period 3-7 months until they mature in to seedlings or commonly called as propagules. The physiological maturity of seeds generally determined on the basis of accumulation of higher dry weight with maximum germination. In Rhizophora macronata physiological maturity of seed determined as 14th weeks after anthesis. The moisture content of the seed was decreased to with increase of dry weight. In Brugeiera cylindrica, the harvestable maturity can be fixed on 12th weeks after anthesis. It was based on the maximum dry weight. 2.4 gm with minimum fresh weight of 4.09 gm. The germination percentage of seeds was also maximum during that period.Seed maturation studies of Rhizophora mucronata indicate that the best collection time prevails from April to June and in Bruguiera cylindrica the best seed collection time prevails from May to July.

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Phenological Study and Determination of Physiological Maturity of Purwoceng Seeds

JURNAL AGRONIDA ◽

10.30997/jag.v4i1.1534 ◽

2019 ◽

Vol 4 (1) ◽

Author(s):

Devi Rusmin ◽

Ireng Darwati

Keyword(s):

Seed Quality ◽

Dry Weight ◽

Germination Percentage ◽

Physiological Maturity ◽

Experimental Station ◽

Seed Maturity ◽

Germination Speed ◽

Research Institute

The experiment was conducted at Gunung Putri Experimental Station and PlantPhysiology Laboratory of Indonesian Medicinal and Aromatic Crops Research Institute(IMACRI), from November 2008 to July 2009. The aim of the experiment was to determinephysiological maturity of Pimpinella pruatjan seed and to study its morphological structures.Observation and sampling using one hundred plants with four replications. Results of theexperiment showed that the physiological seed maturity on the first and third umbell of P.Pruatjan was achieved at 7 weeks after anthesis, and physiological seed maturity on thesecond umbell was achieved at 8 weeks after anthesis. Seed dry weight on the physiologicalseed maturity on first, second and third umbells were 166,87; 158,20, and 141,35 mg/100pericarp, respectively. Germination percentage and germination speed on the first, secondand third umbells were 5,75 % and 0,22 %/etmal; 22,75 % and 0,94 %/etmal; 10,50 % and0,38 %/etmal, respectively.Keywords: flowering, pruatjan, seed quality, morphology

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Influence of Different Light Intensities on the Content of Diosgenin, Lipids, Carotenoids and Fatty Acids in Leaves of Dioscorea zingiberensis

Zeitschrift für Naturforschung C ◽

10.1515/znc-2002-1-223 ◽

2002 ◽

Vol 57 (1-2) ◽

pp. 135-143 ◽

Cited By ~ 2

Author(s):

Huming Li ◽

Alfons Radunz ◽

Ping He ◽

Georg H. Schmid

Keyword(s):

Fatty Acids ◽

Chlorophyll Content ◽

Leaf Shape ◽

Saturated Fatty Acids ◽

Dry Weight ◽

Carotenoid Content ◽

Monoenoic Acid ◽

Hexadecenoic Acid ◽

Dioscorea Zingiberensis ◽

Light Intensities

Cultivation of the climbing plant Dioscorea zingiberensis at a light intensity of 100 μE · m-2 · sec-1 yields three different phenotypes. Most of the plants grow as green phenotype (DzW). Two further forms differ in their leaf shape and leaf color. Whereas one type exhibits a more pointed leaf shape in the upper part of the plant with leaves appearing yellow-green with white stripes or hatchings (DzY), the other type shows a more round leaf shape with an intensive yellow-green color (DzT). These three plant types differ in their diosgenin content not only in their rhizomes but also in the chloroplasts. In the rhizomes the diosgenin content in the green form is 0.4%, in the DzY-form 0.6% and in the DzT-form even 1.3% of the dry weight. Furthermore, even in chloroplasts of the green DzW-form and of the DzY-form the presence of diosgenin was demonstrated. It occurs there as the epimeric form yamogenin. The DzT-form contains no yamogenin in its chloroplasts. Besides this, these plant forms differ in their chlorophyll and carotenoid content and in their fatty acid composition. Carotenoids increase from 1.3% of total lipids in the green phenotype to 3.3% in the DzYand to 4.2% in the DzT-form. This increase refers to _-carotene as well as to lutein and neoxanthin. The chlorophyll content in the green type is 8.1% and lower in the DzY-form with 7%. The highest chlorophyll content is found in the DzT-form with 12%. Fatty acids in the DzY-form and in the DzT-form have a more unsaturated character than in the green phenotype. The content of the monoenoic acid trans-hexadecenoic acid is considerably lower in both phenotypes when compared to the green phenotype. In both phenotypes the quantity of fatty acids with 16 carbon atoms is reduced, whereas fatty acids with 18 carbon atoms occur in higher concentration. Cultivation of the green phenotype (DzW) at the three light intensities of 10, 100 and 270 μE · m-2 · sec-1 leads to changes of the diosgenin content in rhizomes, to an increase of leaf dry weight, to a reduction of the grana structure in chloroplasts and therewith to a decrease of the chlorophyll content. The total lipid content is highest under the cultivation at 100 μE · m-2 · sec-1 and reduced by 30% at 10 and 270 μE · m-2 · sec-1. Carotenoids, however, are highest in shaded plants (10 μE · m-2 · sec-1) and plants grown under high light conditions of 270 μE · m-2 · sec-1. At 100 μE · m-2 · sec-1 a decrease of saturated fatty acids is observed in comparison to plants grown under shaded conditions.

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Effects of Light Condition on Growth and Physiological Characteristics of the Endangered Species Sedirea japonica under RCP 6.0 Climate Change Scenarios

Plants ◽

10.3390/plants10091891 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1891

Author(s):

Kyeong Cheol Lee ◽

Jiae An ◽

Jung Eun Hwang ◽

Pyoung Beom Kim ◽

Hyeong Bin Park ◽

...

Keyword(s):

Climate Change ◽

Chlorophyll Content ◽

Stomatal Closure ◽

Dry Weight ◽

Utilization Efficiency ◽

Carotenoid Content ◽

Climate Change Scenarios ◽

Co2 Absorption ◽

Growth Responses ◽

Cam Plants

This study was conducted to evaluate the physiological and growth responses of Sedirea japonica cultured in chambers under RCP 6.0 and different light conditions. S. japonica was grown in a soil–plant daylight system chamber under two treatments, a control (CO2 = 400 ppm) and a climate change treatment (CCT) (CO2 = 650 ppm, temperature = control + 3 °C), and three different shading treatments (60%, 90%, and no-shading). S. japonica showed the characteristics of typical Crassulacean acid metabolism (CAM) plants. As the shading rate increased, it increased chlorophyll content, leaf area, and leaf dry weight to efficiently absorb and use light. The CCT had a lower CO2 absorption rate, stomatal conductance, and growth rate and slightly higher water utilization efficiency than the control. This was because stomatal closure occurred in the CCT to reduce water loss due to a relatively higher temperature. As CO2 fixation decreased and consumption increased due to respiration, the overall growth was inhibited. The CCT without shading revealed a dynamic photoinhibition phenomenon showing a significant increase in ABS/RC, TRo/RC, ETo/RC, and DIo/RC and a decrease in PI ABS and DF ABS. In this group, leaf, root, and total dry weight, chlorophyll content, and carotenoid content were the worst growth indices.

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Changes in the vitality, lipid peroxidation and hydrogen peroxyde content of maize /Zea mays l./ seedlings during controlled accelerated ageing

Agricultural sciences ◽

10.22620/agrisci.2021.29.013 ◽

2021 ◽

Vol 13 (29) ◽

pp. 110-117

Author(s):

Radoslav Chipilski ◽

◽

Albena Pencheva ◽

Keyword(s):

Hydrogen Peroxide ◽

Zea Mays ◽

Cell Membrane ◽

Chlorophyll Content ◽

Zea Mays L ◽

Germination Rate ◽

Dry Weight ◽

Membrane Stability ◽

Accelerated Ageing ◽

Cell Membrane Stability

Seeds from the maize /Zea mays L./ variety Kneja 310 and landrace B0E0170 were subjected to controlled accelerated aging test (AA) for 72 hours and 120 hours at temperature 41±0.5°C and 100.0% air relative humidity. For the control variant, not subjected to the АА test seeds were used. After AA test, all seed variants were germinated and were used for an analysis of germination energy. The emerging coleoptiles were studied for the presence of anti-oxidative response (MDA, hydrogen peroxide, cell membrane stability), and morphological parameters and relative chlorophyll content were assessed as well as. A vegetation pot experiment was performed with the AA-72h variant and 15-day seedlings were morphologically and physiologically assessed. The aim of the study was to evaluate the relationship between the vitality of the seeds and their stress response to the controlled AA test, which simulated low-temperature storage. The germination rate of seeds and the fresh and dry weight of coleoptiles following ageing treatments were decreased. These results correlated well with the increased accumulation of total hydrogen peroxide and MDA content and the decrease of cell membrane stability. Negative changes were observed in chlorophyll content index, fresh and dry weight and leaf area of 15-day seedlings in pot trial. It was concluded that the controlled accelerated ageing could be used as a model for estimation of seed deterioration in maize after long-term storage.

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Changes in the growth and antioxidant enzyme activity of seedlings originating from wheat seeds subjected to accelerated ageing test

Agricultural Science and Technology ◽

10.15547/ast.2020.03.034 ◽

2020 ◽

Vol 12 (3) ◽

pp. 216-220

Author(s):

R. Chipilski ◽

B. Kyosev ◽

R. Cholakova

Keyword(s):

Enzyme Activity ◽

Antioxidant Enzyme ◽

Chlorophyll Content ◽

Germination Rate ◽

Morphological Characteristics ◽

Dry Weight ◽

Antioxidant Enzyme Activity ◽

Accelerated Ageing ◽

Guaiacol Peroxidase ◽

Wheat Seeds

Abstract. The objective of this study was to investigate the reaction processes of seedlings originating from wheat seeds after they were subjected to accelerated ageing, which imitated low-temperature storage. Germination, vigor, morphological characteristics, relative chlorophyll content and antioxidant enzyme activity were measured in seedlings and young plants of wheat (Triticum aestivum L.) after processes of accelerated ageing of the seeds. The ageing procedures of the seeds were done according to the standard conditions (40±0.5°C and 100% air relative humidity) of the International Seed Testing Association for 72 and 120 hours of treatments of the Bulgarian varieties Geya-1 and Sadovo 772. For the control were used seeds, which were not subjected to the accelerated ageing conditions. The coleoptile of 5 days seedlings and second leaf of 10 and 15 days plants in seedling stage, following the seed accelerated ageing procedure, was measured in the laboratory and the greenhouse. The seed germination rate and vigor, fresh and dry weight of growing coleoptiles were inhibited after different periods of ageing exposure and well correlated with increased accumulation of total hydrogen peroxide, malondialdehyde content, guaiacol peroxidase activity and rate of cells membrane stability index. The negative changes of chlorophyll content index, fresh and dry weight and leaf area of the leaves of young plants descending from aged seeds sowed in pots were found. It was established that the modern variety Geya-1 was more tolerant to the applied ageing condition than the older Sadovo 772. In conclusion, we considered that accelerated ageing could be used as a model for estimation of seed deterioration in wheat after long-term storage.

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Physiological and biochemical changes in cocoa seed (Theobroma cacao L.) caused by desiccation Perubahan fisiologi dan biokimia benih kakao (Theobroma cacao L.) akibat desikasi

E-Journal Menara Perkebunan ◽

10.22302/ppbbi.jur.mp.v68i1.135 ◽

2016 ◽

Vol 68 (1) ◽

Author(s):

Nurita TORUAN-MATHIUS ◽

. RACHMAWATI-HASID ◽

. NURHAIMI-HARIS ◽

Tolhas HUTABARAT

Keyword(s):

Seed Germination ◽

Water Content ◽

Theobroma Cacao ◽

Germination Rate ◽

Dry Weight ◽

Maximum Growth ◽

Growth Potential ◽

Normal Seedling ◽

Theobroma Cacao L ◽

Physiological And Biochemical

Ringkasan Benih kakao tergolong rekalsitran, benihnya sensitif terhadap desikasi dan apabila disimpan pada kondisi yang menyebabkan kehilangan air, benih akan kehilangan viabilitasnya. Viabilitas benih kakao hanya dapat dipertahankan beberapa hari saja dalam keadaan terbuka pada suhu kamar. Hal ini merupakan kendala dalam penyimpanan dan pengiriman benih kakao. Tujuan penelitian ini adalah untuk menetapkan pengaruh desikasi terhadap karakter fisiologis dan biokimia benih kakao. Benih ICS 60 (kakao lindak) dan DR2 (kakao mulia) diletakkan dalam cawan Petri kemudian disimpan pada suhu 25oC dan Rh 55-75% selama empat hari. Percobaan dilakukan dengan rancangan petak terpisah, petak utama adalah kandungan air awal dan kritikal. Sebagai anak petak adalah jenis kakao, masing-masing diulang empat kali. Peubah fisiologis yang diukur adalah viabilitas benih mencakup kandungan air benih, potensi tumbuh maksimum, daya berkecambah, kecepatan tumbuh, bobot kering kecambah normal, dan laju pertumbuhan kecambah normal. Di samping itu juga dilakukan pengamatan pola pita protein benih yang dianalisis dengan SDS-PAGE. Kandungan asam absisik (ABA) dan gula stahiosa, raftnosa, glukosa, fruktosa, arabinosa, silosa, serta sukrosa dalam benih yang ditetapkan dengan HPLC Integritas membran benih ditetapkan berdasarkan daya hantar listrik air perendaman benih yang diukur dengan konduktometer. Hasil yang diperoleh menunjukkan bahwa adanya interaksi yang nyata antara desikasi dengan seluruh tolok ukur fisiologis. Desikasi menyebabkan penurunan daya berkecambah, bobot kering dan laju pertumbuhan kecambah normal, potensi tumbuh maksimum dan kecepatan tumbuh. Sedang untuk, kandungan ABA, sukrosa, arabinosa dan rafinosa mengalami peningkatan. Di samping itu desikasi menyebabkan dibentuknya protein baru dengan BM 32,5; 47,0 dan 51,0 kDa (DR2); 47,0 dan 51,0 kD (ICS 60). Beberapa protein yang hilang oleh pengaruh desikasi yaitu dengan BM37, 0 (DR2), 19, 0 dan 37, 0 kD (ICS60). Benih ICS60 lebih tahan terhadap desikasi dibandingkan dengan benih DR2. Summary Seed of cocoa is recalcitrant and sensitive to desiccation. In open condition at room temperature, the viability of cocoa seed ultimately lost for several days. These characters are a problem for seed storage and delivery. The objectives of this study are to investigate the effect of desiccation on physiological and biochemical characters of cocoa seed. Seeds of ICS 60 (bulk cocoa) and DR2 (fine cocoa) were placed on Petri dishes and stored at 25oC, Rh 55-75% for four days (critical water content). The experiment was conducted with split plot analysis, (1) The main plot was the storage condition initial and critical seeds water content. (2) The sub plot was the variety of cocoa, with four replications of each treatment. The effect of desiccation on seeds viability was tested, based on seed water content, maximum growth potential, seed germination, germination rate, dry weight of normal seedling, and seedling growth rate. Besides, the changes of seed proteins band pattern were also analysed by SDSPAGE. Abscisic acid, stachyose, raffnose, fructose, arabinose, xyllose, and sucrose seed content were determined by HPLC. The integrity of seed membrane based on the leakage of electrolytes from seeds was measured with a CM 100 multicell conductivity meter. The results showed that there is an interaction with highly significant correlation between desiccation and all of the physiological and biochemical parameters. Desiccation caused the decrease of seed germination, dry weight and growth rate'of normal seedling, maximum growth potential, and germination rate and while the leakage of electrolytes, ABA, sucrose, arabinose and raffinose increased. Besides, desiccation was also caused the formation of new proteins with MW 32.5, 47,0 and 51,0 kDa (DR2); 47,0 and 51,0 kD ICS 60) . On the other hand, several protein were disappeared i.e. MW 37,0 (DR2), 19,0 and 37,0 kD (ICS60). Seeds of ICS 60 are more tolerant to desiccation than seeds of DR2.

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